LOS ANGELES (Reuters) - A campaign to require condom use in pornographic film productions in California has collected enough signatures to put a ballot measure before state voters in 2016, organizers said.

The AIDS Healthcare Foundation said in a statement late on Thursday it had amassed more than 371,000 signatures, above the 366,880 threshold set by the state.

The signatures must still be validated by California election officials.

The nonprofit organization's latest campaign is an effort to widen its battle with porn producers, who have resisted calls for condom use on their movie sets.

In 2012, the foundation successfully backed a voter-approved measure in Los Angeles County to force condom use in porn productions locally. But producers fought the measure in court, and officials from the foundation say county officials have been slow to enforce the measure.

"It's only fair that these performers be afforded the same safeguards as other Californians in their workplaces," Michael Weinstein, president of the AIDS Healthcare Foundation, said in a statement.

The measure, if approved by voters on the November 2016 ballot, would mandate state and municipal officials to make sure condoms are used on pornographic film sets statewide.

Historically, Los Angeles, especially its San Fernando Valley suburb, has been a hub of porn production. A number of high-profile X-rated performers in the area have suffered HIV infections, shaking the industry and local health officials.

Nearly a dozen performers were infected with the HIV virus between 2004 and 2014, according to the AIDS Healthcare Foundation.

Leaders of the Free Speech Coalition, a porn industry trade group, in a blog post on Friday took aim at a section of the proposed ballot measure that would appoint a backer of the law to defend it in court against any lawsuit the state attorney general declined to defend.

The blog post accused Weinstein of seeking to become California's "porn czar" through that provision.

In the past, porn producers have said viewers do not want to see condoms in porn because it distracts from their fantasies. They also warned that porn creators will be more likely to move productions out of state to avoid such rules.

To try to further ensure they have enough support for a ballot measure, AIDS Healthcare Foundation officials said they plan to keep collecting signatures, aiming to have more than 525,000 before a Sept. 14 deadline for submitting signatures to election officials.

(Reporting by Alex Dobuzinskis; Editing by Daniel Wallis; and Eric Beech)